More than a married couple, but not lovers.

Third-year high school student Jirou Yakuin hoped to partner with Shiori Sakurazaka of the same class in the mandatory "Couple Practical" course. In this practical, students must demonstrate that they have the necessary skillset to live with a partner of the opposite sex while presenting a certain level of harmony to the video surveillance that grades them.

Unfortunately, random chance put his slightly subdued self into the practical with the person polar opposite to him, the gyaru Akari Watanabe. Akari on the other hand hoped to be paired with her crush Minami Tenjin.

Their hopes are doubly dashed when they find out that Shiori and Minami are assigned together. Thus, they reluctantly decide to cooperate to reach the top ten, which would give them the right to exchange partners if both couples agree. To that end, Jirou steals Akari's first kiss without realizing what he'd done, while giving a hurried good-bye kiss…